Well coming from a raw vegan diet i have to say it is improving significantly!
I had near zero libido not eating animal products (even on what was a very clean diet-my body was very clean).
When i eat lamb my libido is great - i think it is the fat! I feel nourished, happy, and have energy.
I was really tired on on the raw vegan diet and was too tired to even think about such things.
Being nourished and well rested are key to having libido in our house.